Facebook spotted this threat and eliminated spending a mere 1% of its $100 billion market cap.

It was a move weaker Internet giants failed to pull off in their past, leading to disaster.

Yahoo fits this bill in particular. It could have purchased Google for $5 billion and Facebook for $1 billion. Today, Google is worth $200 billion and Yahoo is just under $20 billion.

All this logic, however, has failed to convince some Web 1.0 veterans that Facebook did anything this week but pull a move from Yahoo's 1999 playbook, when it bought Geocities for $3.5 billion and Broadcast.com for close to $6 billion.

So here's a stat you can use to make those people shush.

Instagram has 35 million users. When Yahoo bought Geocities, it had just more than 4 million. Instagram cost Facebook somewhere around $30 per user. Geocities cost Yahoo a stunning $830 per user.

Broadcast.com was also a technology purchase, so the comparison to Instagram isn't completely fair (although Instagram's mobile app is superior to Facebook's), but it's still worth pointing out that Yahoo paid $10,000 per user of that service.